wind power generation

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wind power generation

Postby archie.cowan on January 7th, 2008, 5:45 pm 

I need help calculating the size of wind turbine to generate 12v electricity - I have small fan rotor with c. 6 inch blades which generates c. 1.5v max irrespective of speed of revolutions, how do I work out the required spec for generating 12v in a high wind speed environment? It is important for my project that the physical size/weight of the generating unit is kept as small as possible. All help much appreciated.
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Postby Removed user on January 7th, 2008, 6:34 pm 

Are you stuck using the fan/generator combo that you have? I’d probably look around for a higher voltage output device. Depending on whether your generated power is DC or AC, you could build several types of voltage multiplier circuits to charge a 12V battery then use the battery for direct DC. ... liers.html ... iplier.htm
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Postby pointloop on January 30th, 2008, 1:27 pm 

If you live way out in the boonies why not do some experimenting yourself as I have. The easiest windmill to build is a single blade with a counterweight on the opposite end and balance it. A yoke at the balance point provides freedom for the blade as it will swing in the wind. Much easier to build and very efficient. Take an inch and half tapered cross section dowl for the propeller[ the tapered end is for the blade and a counterwt at the other end] then glue a strip of Styrofoam on the leading edge, and then the trailing edge and sand to form the blade. Then cover the blade with an old bed sheet and sew it in tightly in place, then paint the bed sheep with an outdoor white or whatever latex paint. Use large polyvinyl pipe to make the mast. Use your imagination and you will accomplish the rest of the task.

The easiest mill is downwind. The control vane has to be on the prop side and a tube, the length of the blade...have it run vertically alongside the mast and at the end of the tube install a clamp loosely around the mast and connect the top end of the tube to the turret. connect a vertical shaft to the end nearest the clamp [it swivels] and a vertical shaft to the vane made of the same material as the blade.

This will power a truck alternator and provide useful power. I built a mill like this years ago and was amazed at the power it has even in winds as little as 5mi/hr. Durability is not an issue cost is. Don't run the mill in strong winds as I did it's horrifying. The shaft must be belted up to increase the rpm...I added a clutch to make it start easier. The version I made years ago had a 16 foot sweep of the blade and mounted on a telephone pole. I did this when I was younger on my dads farm. I'm building a smaller version now.
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Re: wind power generation

Postby bellyballot on March 11th, 2017, 2:26 am 

The wind generator is ideally suited for one 12 Volt, 21 Amp Hour sealed lead acid battery. And the turbine generators are used primarily for electricity generation.
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Re: wind power generation

Postby neuro on March 11th, 2017, 8:17 am 

I may well be wrong, but I believe that the size of the rotor and the rotating speed do not influence the output.
The point is the electromagnetic converter, the motor you use as a dynamo/alternator: the rotating magnets produce an electromotor force (i.e. electric potential) which depends on the number of coils of electric wire that surrounds them. The current they can produce this way will depend on the rotation speed, and therefore on the size of the fan and the strength of the wing. But not the potential.

It is like imagining a 1 kg weight sitting on a 1 cm² transverse-area piston: it will generate a pressure of 1 kg/cm²; then if you raise it 20 times per second you certainly can pump more water out of the syringe than if you only raise it 2 times per second, but the pressure it can generate will never exceed 1 Kg/cm².

Still, I may be wrong...
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